When you think "over the top," you don't immediately think "El Campo."

But the small town about 70 miles southwest of Houston, known for its farming history and immigrant heritage, is home to the world's largest backyard swimming pool.

Built in 2009 by Kuykendall Custom Pools Inc. in Conroe, the resort-style pool belongs to Mike Mobley and his family, who have shared the amenity with the community.

"They're fabulous people," Cheryl Kuykendall, pool company co-owner with her husband, Rick Kuykendall, said of the Mobleys. "They're very generous. The pool has been a good thing for everybody."

With its 21-foot water slide, two hot tubs, sunken bar, outdoor kitchen, six water falls and 500-foot "lazy river," the $3 million pool is a popular weekend destination, she said.

The Mobleys, longtime El Campo residents, have given the Kuykendalls permission to talk about their amazing creation, built on the site of a two-acre pond.

"We build a lot of pools where we have to sign confidentiality agreements," Cheryl said. "We love it when we get clients like the Mobleys."

The Kuykendalls came to the realization that the pool was no doubt the world's largest on residential property when the project was well under way and Mike Mobley, who works in the oil and gas industry, said, "It's not big enough."

"When you're building something that you already think is pretty big and you're told it's not big enough, your mouth is pretty much on the floor," Cheryl said. "That's when my husband started looking around, doing Internet searches to see what was out there."

By comparison, a typical backyard pool is 16,000 to 20,000 gallons, Rick said. The Mobleys' holds 600,000 gallons, which is less than the 750,000 gallons they started with.

They removed some water not to scrimp but to give the lazy river an optional faster speed, Cheryl said. Some new, stronger pumps were installed, and the bottom was raised to reduce the load on them, she said.